At least one embodiment relates to an electrical connector or connector assembly having a plurality of contacts arranged in a grid, and shields disposed among and between the contacts for minimizing electrical crosstalk in the connector.
Plug-in circuit boards with electronic components thereon are widely used in the telecommunication and computer industries, among other industries. High speed data signals are conveyed to and from the circuit boards at a desired data rate using cables and connectors. The data signals are comprised of multiple frequency components, each frequency component of which is attenuated to a differing degree by the cables, connectors and circuit boards.
Such circuit boards require carefully designed transmission paths to minimize interference and preserve signal integrity. As switching speeds increase, minimizing interference and preserve signal integrity. As switching speeds increase, minimizing interference and preserving signal integrity becomes more critical. To address such concerns, high frequency (low inductance) connecters have been developed for use with such circuit boards.
Conventional high frequency connectors employ shielding to minimize interference and preserve signal integrity. Such shielding is arranged on the connectors to shield contacts on the connectors from neighboring contacts reducing or minimizing crosstalk, preserving signal integrity.
U.S. Pat. No. 4,846,727 discloses an electrical connector including an insulating housing have a plurality of electrical contacts arranged in a grid of horizontal rows and vertical columns. Electrically conductive plates are disposed between the columns and are adapted for connection with an electrical reference or ground, thereby providing shield elements between the columns of contacts. These shield elements serve to prevent electrical crosstalk between contacts in adjacent columns.
U.S. Pat. No. 5,620,340 discloses an electrical connector including contacts arranged in a grid, and shielding elements that have a non-planar shape. These shielding elements may have a square-wave, serpentine, or other meandering shape to substantially shield each of the contacts from all neighboring contacts, including neighboring contacts in the same column.
A need exists for an electrical connector with improved shielding. There is a further need for improved shielding between the contacts in an electrical connector wherein the contacts are arranged in a high-density grid and wherein the improved shielding reduces or minimizes electrical crosstalk, signal to noise ratio and jitter signal to noise ratio. It is an object of at least one embodiment of the present invention to meet the foregoing needs and other objectives, which will become apparent from the detailed description, drawings and claims presented hereafter.
In accordance with one embodiment of the present invention, an electrical connector or connector assembly has been developed with improved shielding that reduces or minimizes interference and electrical crosstalk, preserving signal integrity. The connector in accordance with at least one embodiment of the present invention employs first and second shield members to isolate each of the contacts from neighboring contacts. The connector holds a plurality of contacts arranged in rows and columns. First shield members are disposed in the housing between the contact rows, and second shield members are disposed in the housing between the contact columns.
In accordance with at least one embodiment of the present invention, the first and second shield members electrically shield each of the contacts on at least two sides from neighboring contacts.
In accordance with at least one alternative embodiment of the present invention, the plurality of contacts comprises a plurality of interior and exterior contacts, where the interior contacts are electrically shielded on four sides from neighboring contacts. A pair of first and second shield members shields each of the interior contacts from neighboring contacts. The first shield members are made of an electrically conductive material and comprise a single unit extending along at least two adjacent rows of contacts removably engaging a mating electrical connector. Each of the second shield members mechanically engages at least one of the first shield members, preferably electrically connecting to at least one of the first shield members.
In accordance with at least one alternative embodiment of the present invention, the second shield member is made of an electrically conductive material and is generally planar in shape. The second shield member has a generally planar main body and at least two resilient arms extending from opposing sides of the main body and adapted to be deflected within a plane of the main body. A portion of each of such main body is adapted to overlap a portion of one or more respective contacts, electrically shielding the contacts from any neighboring contacts.
In yet another embodiment, the first and second shield members are formed of an electrically conductive material selected from a group consisting of sheet metal, copper, nickel, zinc, brass and the like. The first and second shield members, or portions thereof, may be made of the same or different material.
In an alternate embodiment, the second shield members engage at least one of the first shield members. At least one of the second shield members is disposed between two first shield members, the second shield members having a pair of arms that engage the first shield members.
In accordance with yet another alternate embodiment, the housing is made of an insulating material, having front mating and opposing mounting faces. The housing defines a plurality of slots, wherein each of the second shield members is disposed in respective slots.
In accordance with yet another alternative embodiment, each of the contacts has a mating section adapted to engaging mating portions of a mating electrical connector. Each contact includes a pair of resilient beams adapted to engage mating portions of a plurality of contacts in the mating electrical connector. Further, each connector has a mounting section adapted to engage a circuit board.
Yet another alternate embodiment of the present invention includes an electrical connector used with a circuit board for carrying high speed data. In this embodiment, the connector includes a plurality of electrically conductive members in a housing arranged in a grid and means for electrically shielding each of the conductive members from neighboring conductive members on at least two adjacent sides.
In an alternative embodiment, the electrical connector used with a circuit board comprises a plurality of interior and exterior contacts, each of the interior contacts are electrically shielded from neighboring contacts on four sides. The shielding means comprise first shield members disposed in contact rows and second shield members disposed in contact columns in the grid, such that the second shield members engage neighboring first shield members. Each of the interior contacts are shielded from neighboring contacts by a pair of the first shield members and a pair of the second shield members.
Another alternative embodiment in accordance with the present invention includes a method of transmitting high speed data signals through an electrical connector. The electrical connector has engaging first and second shield members. The data signal is transmitted at a predetermined data rate greater than about 2 gigahertz and with a predetermined signal to noise ratio. Data is further transmitted through the connector at a high speed with a predetermined jitter signal to noise ratio.